Pixel arrays in display devices are mainly divided into two kinds, a full color pixel array, and a sub-pixel rendering pixel array.
The full color pixel array includes a plurality of pixel units, as shown in FIG. 1a, each pixel unit includes three sub-pixels (i.e. a red sub-pixel, a green sub-pixel and a blue sub-pixel), and the three sub-pixels in each pixel unit have the same size.
The sub-pixel rendering pixel array also includes a plurality of pixel units dividing into two kinds of pixel units, as shown in FIG. 1b, one kind of pixel unit includes a red sub-pixel and a green sub-pixel, and the other kind of pixel unit includes a blue sub-pixel and a green sub-pixel, and each pixel unit includes two sub-pixels.
For the full color pixel array, each pixel has a too small size, and thus its fabrication is more difficult. For the sub-pixel rendering pixel array, the number of the sub-pixels is reduced, but the green sub-pixel has a smaller size. The minimal dimension of the mask plate for manufacturing the pixel array is the width of the green sub-pixel, and thus the minimal dimension of the mask plate is very small, which will easily lead to degradation.
Therefore, how to improve the minimal dimension of the mask plate so as to reduce degradation becomes a technical problem to be solved in this field.